Questions and answers Morphology of stem and shoot
Introduction to Botany. Lecture 12
Alexey Shipunov
Minot State University
September 23rd, 2011
Shipunov BIOL 154.12 Questions and answers Morphology of stem and shoot Outline
1 Questions and answers
2 Morphology of stem and shoot Plant body Components of shoot Branching Phyllotaxis
Shipunov BIOL 154.12 Questions and answers Morphology of stem and shoot Outline
1 Questions and answers
2 Morphology of stem and shoot Plant body Components of shoot Branching Phyllotaxis
Shipunov BIOL 154.12 3
Questions and answers Morphology of stem and shoot Previous final question: the answer
Where is a cambium?
Shipunov BIOL 154.12 Questions and answers Morphology of stem and shoot Previous final question: the answer
Where is a cambium?
3
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Types of plant body
Thallous (flat, with non-differentiated organs) Shoot body (roots are absent) Bipolar body (root and shoot systems)
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Organs of bipolar plant
Leaf: flat lateral organ with restricted growth Stem: axial aerial organ with continuous growth Root: soil organ modified for absorption Floral unit (FU): stable element of generative system
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Pseudo-organs
Hypocotyl: transition between stem and root Epicotyl: first internode of plant Bud: shoot “embryo” Fruit: temporary structure, ripe FU Seed: chimeric structure, has two or three genotypes
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Hypocotyl and epicotyl
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Organ systems
Vegetative shoot system Generative shoot system Root system
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Organs vs. organ systems
... Vegetative Generative Root system shoot shoot system system
Leaf + + −
Stem + + ±
Root ± ± +
FU − + ±
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Components of vegetative shoot system
1 Main and secondary shoots 2 Terminal and axillary (lateral) buds 3 Nodes and internodes 4 Leaves
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Components of shoot
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Winter shoot
1 Vegetative, flower, and mixed buds 2 Leaf and bud scars 3 Leaf traces
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Winter shoot of maple (Acer platanoides)
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Types of branching
Monopodial: buds do not degrade, all shoots continue to grow Sympodial: terminal buds degrade, the lateral shoot closest to terminal bud becomes terminal shoot
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Monopodial (left) and sympodial branching
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Arrangement of leaves: phyllotaxis
One leaf per node: spiral arrangement Two leaves per node: opposite arrangement, they may be: All in same plane Each pair will rotate on 90◦ > 2 leaves per node: whorled arrangement (each whorle can also rotates) Each type of phyllotaxis has its own angle of divergence
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Angles of divergence
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Spiral phyllotaxis 1
Multiple types of leaf spiral leaf arrangement mostly follow Fibonacci rule Formulas of leaf arrangements is very similar to Finobacci 1 1 2 3 5 fractions: 2 , 3 , 5 , 8 , 13 , et cetera* Numerator is number of spiral circulations, denominator is number of leaves
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Summary
It is possible to divide plant body to different organs and/or organ systems Bud, fruit and seed are pseudo-organs Sympodial branching is evolutionary more advanced than monopodial Spiral arrangement of leaves follows Fibonacci rule
Shipunov BIOL 154.12 What is the difference between monopodial and sympodial branching?
Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Final question (1 point)
Shipunov BIOL 154.12 Plant body Questions and answers Components of shoot Morphology of stem and shoot Branching Phyllotaxis Final question (1 point)
What is the difference between monopodial and sympodial branching?
Shipunov BIOL 154.12 Appendix For Further Reading
For Further Reading
J. E. Bidlack, Sh. H. Jansky. Stern’s introductory plant biology. 12th edition. McGraw-Hill, 2011. Chapter 6.
Th. L. Rost, M. G. Barbour, C. R. Stocking, T. M. Murphy. Plant Biology. 2nd edition. Thomson Brooks/Cole, 2006. Chapter 5.
Shipunov BIOL 154.12